Return bend fitting for oil stills



March 2, 1937. F. c. FANTZ RETURN BEND FITTING FOR OIL STILLS 4 Sheets-Sheet 1 FIG] INVENTOR y/cnpd.

ATTORNEY Filed Deb. 8, 1931 March 2, 1937. F. c. FANTZ RETURN BEND FITTING FOR OIL STILLS Filed Dec. 8, 1931 4 Sheets-Sheet 2 FIG. 5.

FIG. 8.

INVENTOR JM Z/ BY 7 %v%a/ W ORNEY March 2, 1937. F. c. FANTZ RETURN BEND FITTING FOR OIL STILLS Filed Dec. 8, 1931 4 Sheets-Sheet 5 FIG: /2.

INVENTOR 0 a, BY

RNEY

March 2, 1937. F. c. FANTZ 2,072,669

RETURN BEND FITTING FOR OIL STILLS Filed Dec. 8, 1931 4 Sheets-Sheet 4 INVENTOR ?atented Mar. 2, 1937 RETURN BEND FITTING FOB OIL STILLS Fred (2. Fantz, Webster Groves, Mo.

Application December 8, 1931, Serial No. 579,707

7 Claims.

My invention relates more particularly to that class of stills in which the tubes are subjected to high pressures and temperatures. It is .well known that in cracking stills of this type some of these-tubes last only 5 or 6 weeks and when the tubes are rolled into the return bend (as is done in the majority of cases) the tube becomes a part of the bend so that it is necessary, in removing one tube, to destroy the one next to it regardless 0 of its condition.

Inasmuch as these tubes are removed and reconventional type of junction boxes, prior to my invention the tubes were rolled into the headers but in order to do this an opening in the back of the junction box or header had to be provided so that the tube rolling devicecould be inserted to roll the tube in. This opening was later closed,v

either by a screwed plug or some other method of holding aplug in place. This plug was then removed in order to clean out the tubes and to make aninspection of the inside of the tubes. Naturally this inspection could not be verythorough, as the inspector was looking through a tube approximately 20 ft. long, making it difiicult, if not impossible to see any smallimperfect part which was down a considerable distance of the length of the tube. When tubes are rolled into the return bend or headers the entire coil bank becomes in eifect one solid piece, then inspection of the outside of the tube was-limited to that part which could be seen from the top or bottom.

Therefore onlya superficial inspection could be 40 madeof the tubes in the center of the bank. It

. follows therefore that tubes are either cut out before the' full life of the tube or else achance is taken and the tubes are run longer than they shouldbe, frequently resulting in a rupture of tubes during the operation, thus causing severe damage to the equipment from fire.

My invention has for its principal object to provide a return bend fitting in'which the tubes are by providing quick and easy access to the interior of the tubes for the purpose of cleaning, the accumulation of coke from. their interior. It will be clearly seen that any tube can be removed' for thorough inspection and placed back eitherin the same position or in a less hazardous part of the bank, depending upon the relative life of the tube, this also makes possible av comparatively slight of the I In theconstruction of stills, which utilize the I 5 loss of time entailed for the inspection of any tube regardless of its location in the bank or nest and also permits its rotation if the tube is bent or has sagged during the operations. u

A further object of my invention is to provide 5 .a return bend fitting which will permit of its mounting on tubes in close centers, it b'eingwell known to persons skilled in the art that the tubes in these coil banks or nests are mounted so close 5 together that the space provided for the return bend fitting is very limited. It is therefore essential for a satisfactory commercial bend that it be so designed as to permit of its being mounted and removed within the exceedingly close limits afforded by the positions of the tubes in the nests or banks. 4

My means of accomplishing the foregoing objects may be more readily understood byhaving reference to the accompanying drawings, in whichv Fig. 1 is a side elevation of my improved return bend, part of the wall being broken away to show the interior construction; the tube spacing member being shown mounted in the tube sheet of the still;

Fig. 2 is a detail view of the return bend proper;

Fig. 3 is a detail view of two complementary parts of thecompoundshousing; r

' Fig. 4 is a vertical sectional view through a tube, return bend proper and the housing sections Fig. 5 is a similar view showing the housing members in contact with the shouldered portions v on the tube;

Fig; 6 .-is a similar view showing a modifiedlform of fastening for holding the sections together;

Fig. 7 is a fragmentary view of a tube sheet showing my improved means for holding the tubes in spaced relation;

Fig. 8 is a detail view of this connecting member;

Fig. 9 is a side elevation of the same;

Fig. 10 is a vertical sectional view of a modified form of housing;

Fig. 11 is a similar view showing the housing sections contacting the shoulders on the tube, means'which lock the sections of the housing together being omitted;

Fig, 12 is a vertical sectional view showing a 1 modified form of securing means for producing a tight joint for the return bend and tubes; '50 Fig. 13 is a plan view of means for securing the housing sections ,together;

Fig. 14 is an enlarged fragmentary detail view showinghow the complementary sections may be held together; I 65 Fig. 15 is a vertical sectional view showing'a modified form 01 construction; and 1 m Fig. 16 is a perspective view of an. installation of my return bend fitting on a still, the outer door being open showing the coil orbank and a number of the tubes equipped with my return bends a portion of the tube sheet being shown without any bends so as to show the construction of the tube sheet.

Similar reference numerals refer tosimilar parts throughout the entire description.

As shown in Figs-1 to 4 I have illustrated a fragmentary portion of the still tubes i and 2, as obviously my invention pertains only to the ends of these tubes. Therefore there is no necessity for showing the entire tube. These tubes are connected to, and in communication with, a return.bend 3 mounted in a compound housing.

This return bend is provided with abutments and 5, the purpose which will be hereinafter explained. The face 6'of the return bend is tapered inwardly and upwardly and adapted to contact a correspondingly tapered portion 1 formed on the face or end of the shoulders flwhich are formed on the ends of the tubes. Itis apparent that any form of joint desired may be used without affecting the invention or its operation.

As shown in Figs. 1 and 4, these shoulders are comparatively small as a small flange or shoulder is much more quickly and inexpensively upset on a tube thanone wherelthe shoulder extends longitudinally for some considerable portion of the a on the tube.

-on the tube, the lower edge of the-sleeve 9 is tube. Although I have shown the shoulder as an integral part of tube it is apparent .that it may be attached to the tube if desired. When the heavy shoulder'is employed it is generally ,done for strength and I accomplish the. same result by fitting a reinforcing ring or sleeve9 This sleeve contacts the shoulder undercut as at Ill and adapted to receive inwardly and upwardly projecting extensions ll formed on'the lower end of the housing sections which hold the housing sections together.

The "compound housing is constructed, as shown, of complementary sections I2 and 13, one pair for each tube, as shown there are four of these sections but it will be obvious that they can beformed in two sections or connected in any manner desired without departing .-f1om the scope of my invention. These complementary sections l2 and i3 are provided with inwardly extending arcuate flanges M which are adapted to'contact the exterior wall of the tubes 9 and 2, the extensions H which engage, the undercut portions of the sleeve 9 are formed integral with the arcuate flanges and thus interlock them with said ring or sleeve 9. .If the housing sections 92-42 and i3 i3 are to be connected the hous- 5 ing sections should be madeas shown in Figs. 10,

11 and 12. One way in which this could be accomplished is shown-in Fig. 15 in which I provide a a set screw w ch is long-enough so that housing section 6 3 can he slid downwardly along the tubes enough to release the boss I 5 from the laterally extended portion i1 thereby removing both parts without the necessity of swinging them to the position shown in Fig. 3 which, of course, is impossible if they are made in halves and also without the necessity of tapering the side Wall of the aperture l8. One of the housing sections 13- is provided with internal threads in which is mounted a set screw H5. The other housing sec- Y tion 82 is provided with a laterally extending portion .|1in which is formed an aperture. I8 which fits the boss l5 formed on the housing section l3. The inner ends of the set screws l6 are adapted to, engage the abutments 4 and 5 formed on the return bend 3 for that purpose. In

' some cases it may be found desirable in practice fitted to the ends of the tubes.

the undercut portions of the sleeve 9, the sec-.

tions are then swung into position shown in Fig. 1, and the set screws tightened. This operates to draw the tubes'upwardly against the tapered face of the return bend making an effectual leakproof joint. I

It will at the same time be obvious that it is a comparatively simple matter to remove the housing sections, by loosening the set screws, when the return bend can be lifted off the tubes and the tubes are then free to be removed either for inspection or replacement, without destroying any part of the apparatus; or for turning over a tube that has become corroded or damaged on one side.

In Fig. 5 I have shown a modified form of construction in which the ring or sleeve 9 is omitted and the shoulder 23 is provided with an undercut portion 24 adapted to receive the extensions ll. When this form of construction is used it is desirable to have the'shouldered portion of the tube substantially thicker than where the reinforcing sleeve 9 is provided.

In Fig. 6 the housing sections I2 and I3 are provided with extensions 25 which are adapted to be engaged by a ring 26 which serves to hold for the upwardly extending extensions H and the undercut portion on the shoulders is avoided. For as will be clearly seen by those skilled in the art they are equivalent since the ring in both cases holds the sections together.

It is well known to persons skilled in the art that the holes, in the tube sheet I9, (a fragmentary portion of which is shown in Fig. '7) ..of the still (not shown) are larger than the tubes themselves with the result that the tubes frequently spring out of place and it is desirable to provide meansvto hold them in alinement and 'alsoin spaced relation, because only by so doing can the .U-piece or return bend 3' be conveniently I accomplish this by means of the device shown in Figs. 8 and 9 in which I provide a plate having substantially circular openings 20 therein which are fitted to the outside \of the tubes 3 and 2. projecting flanges H which are eccentric to the substantially circular. openings 20 and which fit the openings in thetube sheet 19 with the result that when this plate 22 is placed on the tubes and then the flanges 2| are driven into the tube sheet the tubes are held in fixedly spaced relation and their alinement is ensured. 1

In Fig. 10 I have shown the construction so far as the interlocking features of the housing sections with the tubes are concerned which is the same as Figs. 1 and 4 but in this construc tion I form the aperture l8, in the lateral extension I! of the housing sections I2, with an 'outwardly flaring wall as clearly seen at 28. This form of construction permits the housing-sections to be swung outwardly as seenby the These plates have dotted linesin Fig. 10 thus facilitating the disengagement of the housing sections with the undercut portions of the slee ves 9.

In Fig. 11 the same construction is shown, but the housing sections are shown in actual contact with the shoulders formed on the tubes, the sleeve 9 being omitted. In, this view the means for securing the housing sections together is also omitted.

In Fig. 12 I have shown a form of construction in whichI provide an extension 29 on the housin'gsection 3|, the outer surface 30 of which is tapered and to which is fitted a ring 33 having I its walls correspondingly tapered. By forcing this ring 33 on the tapered extensions of the housing sections they are held firmly in place. In this form I have showna standard arrangement for mounting the set screw 34, it being carried in a plate 35, the ends of which extend into slots or openings formed in the housing sections. -'Ihe function of this manner of mounting the set screw it with the structure already described, is identical, it being merely a well known variation in the form of mounting employed for that purpose in the art.

:Although I have shown and described the rings 26 and '33 as being formed in two pieces it will be obvious to persons skilled in ,the art that they may, if desired,be constructed as shown in Fig. 13 in which the rings are joined by a web, or a plate 36 may be provided, which has apertures 31 and 38 which fit the extensions on the housing sections so as to hold'them together. Suitable means (not shown) for holding this plate in position may be provided if desired.

In Fig. 14 I have shownan enlarged fragmentary detail view in which the undercut portion of the sleeve 9 is considerably deeper than shownin the other figures of the drawings and the extensions H are correspondingly greater. -It is plainly apparent that this is merely a mechanical variation of the structure and in nowise differs from the scope of the invention.

While I have described with some degree of particularity specific forms for theembo'diment as new and desire to secure by Letters Patent is:

1. In a refinery apparatus, a-return bend, a pair of shouldered tubes-communicating therewith, a compound housing therefoncomprising complementary sections each adapted to. partially encircle the ends of said tubes, upwardly and inwardly extending flanges on the lower ends of said sections adapted to be locked to the shoulders on the tubes, detachable means mounted in said housing sections to hold said tubesand returnv bend in a tight joint, and a sleeve on each of said tubes intermediate the shoulders on the tubes and the housing sections.

' 2.- Irra refinery apparatus, a return bend, a pair of shouldered tubes communicating therewith, a compound housing therefor, comprising complementary sections each adapted to partially encircle the ends of said tubes and to be locked to the shoulders on" the tubes, detachable means mounted in said housing sections to hold said tubes and return bend in a tight joint, a. sleeve on each of said tubes intermediate the shoulders on the tubes and the housing sections, the lower surface of the sleeves being undercut.

3. In a refinery apparatus,a return bend, a pair of shoulderedtubes communicating therewith, a compound housing therefor, comprising comple mentary sections each adapted to partially encircle the ends of said tubes and to be locked to the shoulders onthe tubes, detachable means mounted in said housing sections to hold said tubes and return bend in a tight joint, a sleeve on each of said tubes intermediate the shoulders on"the tubes and the housing sections, the lower surface of the sleeves being undercut, extensions on said housing sections which contact said tubes, and engage said undercut to hold said sections together.

4. In a refinery apparatus, a return bend, a pair of shouldered tubes communicating therewith, a compound housing therefor, comprising complementary sections adapted to partially encircle the ends of said tubes and to be locked to the shoulders on the tubes, a boss on one of said complementary sections there being an aperture in the other section in which said boss is mounted, and a set screw in said boss which contacts said return bend.

5. In a refinery apparatus, a return bend, a pair ofshouldered tubes communicating therewith, a compound housing therefor, comprising complementary sections each of which is adapted to partially encircle the ends of said tubes and to be locked to the shoulders on the tubes, detachable means mounted in said housing sections to holdsaid tubes and return bend in a tight joint and means to hold said tubes in fixedly spaced relation, said means comprising a plate having a pair of openings adapted to straddle the tubes, flanges in the inner side of said plates eccentric to the tubes and fitting openings in the tube sheet.

6. In a refinery apparatus, a return bend, a pair of shouldered tubes communicating therewith, a compoundhousing therefor, comprising complementary sections each adapted to partially encircle the ends of said tubes, upwardly and inwardly extending flanges on the lower ends .of said sections adapted to be locked to the shoulders on the tubes, detachable means mounted in said housing sections to 'hold said tubes and return bend in a tight joint, means to hold said housing sectionstogether, and means to hold said tubes in fixedly spaced relation.

'7. In a refinery apparatus, the combination with a return bend adapted to connect a pair of tubes, each having a shoulder adjacent its end,

I of a compound housing therefor comprising housing sections each adapted to be locked to the shoulders on the tubes, detachable means mounted in said sections to engage said return bend, means for holding the tubes in alinement and in fixedly spaced relation, said means comprising a plate having a pair of openings adapted to straddlethe tubes, flanges in the inner side of said plates eccentric to the tubes and fitting openings in the tube sheet, and means to hold said sections together.

FRED C. FANTZ. 

